The present disclosure relates to a method of scanning a touch panel and a touch integrated circuit (IC) for performing the same. More particularly, the present disclosure relates to a method of scanning a touch panel to recognize a touch signal by a user and a touch IC for performing the same.
A touch panel may be used as an input device of a smart device that includes a display panel and an application processor. The touch panel may be classified into a resistive type, a capacitive type, or an electromagnetic type and the like.
For example, a touch panel of a mutual capacitance type may detect a touch location by measuring a mutual capacitance varying by the touch of a conductor between a driving line and a sensing line.
The touch panel of the mutual capacitance type may include a plurality of driving lines and a plurality of sensing lines crossing the driving lines. When driving signals are sequentially supplied to the driving lines, a mutual capacitance generated by the applying of the driving signals may be detected from the sensing lines. The driving lines and the sensing lines may be connected to a touch IC, and the touch IC may supply the driving signals and obtain sensing signals from the sensing lines.
The touch IC may sequentially supply a driving signal to the driving lines, and sensing signals may be acquired from the sensing lines while the driving signal is supplied to each of the driving lines. At this time, a driving time indicates the amount of time that the driving signal is supplied to one driving line, and a frame time indicates the time required to acquire sensing signals constituting one frame. That is, the frame time is calculated by multiplying the driving time by the number of the driving lines.
Meanwhile, when the driving time is increased, the noise of the sensing signals may be decreased, but the frame time may be increased. As a result, the response time of the touch panel may be increased, and further the response characteristics of the touch panel may be deteriorated. On the contrary, when the driving time is decreased, the frame time and the response time may be shortened. However, the noise of the sensing signals may be increased, and thus it may be difficult to accurately recognize a touch by a user.